# -*- coding: utf-8 -*-
"""
sigmoid函数
Created on Tue Apr 17 09:02:19 2018

@author: Allen
"""

import numpy as np
import matplotlib.pyplot as plt

def sigmoid( t ):
    return 1 / ( 1 + np.exp( -t ) )

x = np.linspace( -10, 10, 500 )
y = sigmoid( x )

plt.plot( x, y )
plt.show()

